In general, a mobile station decodes a part of control channels to request and receive control signals and data signals. A channel to be decoded for control and data signals is usually determined according to communication specifications. For example, a mobile station compliant with IEEE (Institute of Electrical and Electronics Engineers) 802.16m specifications requests and receives control and data signals by decoding A-MAP (Advanced MAP). Also, a mobile station compliant with the 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) specifications requests and receives control and data signals by decoding a PDCCH (Physical Downlink Control Channel).